How to change a guns firerate?

I made a gun script that only fires one bullet per click, how would I change it so that it would be automatic(meaning that i can hold the fire button to make it shoot automatically)

local Player = game.Players.LocalPlayer
local Character = Player.Character or Player.CharacterAdded:wait()
local Camera = workspace.CurrentCamera
local tool = script.Parent
local player = game:GetService("Players").LocalPlayer
local Ammo = script.Parent:WaitForChild("Ammo")
tool.Equipped:connect(function(mouse)
print("Tool equipped!")
holdanim = player.Character.Humanoid:LoadAnimation(script.Parent.HoldAnim)
reloadanim = player.Character.Humanoid:LoadAnimation(script.Parent.ReloadAnim)

    mouse.Button1Down:connect(function()
        if Ammo.Value >= 1 then
        print("Mouse pressed!")
        Ammo.Value = Ammo.Value - 1
        print(Ammo.Value)
        script.Parent.Handle.Fire:Play()
        local ray = Ray.new(tool.Handle.CFrame.p, (mouse.Hit.p - tool.Handle.CFrame.p).unit * 300)
        local part, position = workspace:FindPartOnRay(ray, player.Character, false, true)

        local beam = Instance.new("Part", workspace)
        beam.BrickColor = BrickColor.new("Gold")
        beam.FormFactor = "Custom"
        beam.Material = "Neon"
        beam.Transparency = 0.99
        beam.Anchored = true
        beam.Locked = true
        beam.CanCollide = false

        local distance = (tool.Main.CFrame.p - position).magnitude
        beam.Size = Vector3.new(0.3, 0.3, distance)
        beam.CFrame = CFrame.new(tool.Handle.CFrame.p, position) * CFrame.new(0, 0, -distance / 2)


        game:GetService("Debris"):AddItem(beam, 0.1)

        if part then
            local humanoid = part.Parent:FindFirstChild("Humanoid")

            if not humanoid then
                humanoid = part.Parent.Parent:FindFirstChild("Humanoid")
            end

            if humanoid then
                humanoid:TakeDamage(math.random(10,30))

            end
        end
        end
        end)
end)

local Player = game.Players.LocalPlayer
local action_reload = false
Mouse = Player:GetMouse()

Mouse.KeyDown:connect(function(Key)
    if(Key:lower() == "r") and Ammo.Value < 7 and action_reload == false then
        action_reload = true
        script.Parent.Handle.Reload:Play()
        reloadanim.Looped = false
        reloadanim:Play()
        wait(2)
        Ammo.Value = 7
        print(Ammo.Value)
        action_reload = false
    end
end)

function onEquipped()
    holdanim:Play()
end

script.Parent.Equipped:connect(onEquipped())
mouse = Player:GetMouse()
action_aim = false
mouse.Button1Down:connect(function()
    if action_aim == false and action_reload == false then
        action_aim = true
print("trying to aim")
       repeat wait()
    Camera.CameraType = Enum.CameraType.Scriptable
until Camera.CameraType == Enum.CameraType.Scriptable
Camera.CFrame = script.Parent.AimPart.CFrame
print("aiming")
    end
end)